Hello,
I am trying to flash the latest build for Pixel 7 Pro (2022101800) but at some point the phone bootloops with the google logo and doesn't go further.
In the terminal I get the following error:

extracting vendor_boot.img (64 MB) to disk... took 0.185s
archive does not contain 'vendor_boot.sig'
Sending 'vendor_boot_b' (65536 KB)                 OKAY [  2.240s]
Writing 'vendor_boot_b'                            OKAY [  0.074s]
extracting super_empty.img (0 MB) to disk... took 0.000s
Rebooting into fastboot                            OKAY [  0.000s]
< waiting for any device >
fastboot: error: Failed to boot into userspace fastboot; one or more components might be unbootable.
Rebooting into bootloader                          OKAY [  0.000s]
Finished. Total time: 0.051s

The Pixel is on latest stock rom version and I am using the android-tools 33.0.3 packaged by Arch.
Is it a known issue and is there a fix for this?

EDIT: The error appears because I try to access fastboot by maintaining VOL_DOWN after several loops

    qontinuum Ditto. I used the web installer on my Pixel Pro 7 and did not encounter any issues, either with the initial install, or the update I received yesterday morning.

    I had the exact same problem with the PowerShell (batch file) installation, so there is an issue with that installation or with a Google driver or the Tools. Not sure where the problem is, though.

    On a whim, I tried the web installer and it worked fine.

    But I think there's another problem with the installer. When I tried to restore the phone back to a factory image, it says there's a file missing (that I assume should be there) and it quits.

    Okay, I did some experimenting with trying to restore the Google ROM image, and it failed. On a thought, I decided to search for the latest Platform-Tools, and mine was 5 months(!) out of date. I downloaded and installed the most recent Platform-Tools and everything worked fine: I reinstalled the Google ROM image and I installed GrapheneOS without issue.

    If I wasn't clear in my prior posts, I use the Powershell from Windows to install both the Google ROM and the GrapheneOS images. While the browser installer worked just fine, I like the command line better.